Terrestrial amphipods or “lawn shrimp” are pests that many of you have seen but probably don’t know by name. It is common to see dozens of them on sidewalks, patios and migrating into homes after a heavy rain in Orange County.
These small pests are usually about ½ inch long, are pinkish/brown in color and have a “shrimp-like” form. Look close and you’ll see they have two pairs of antennas, two eyes and they have leg-like appendages.
Lawn shrimp are scavengers and are usually found living under stones or decayingvegetation. They do not have a waxy layer of protection over their body as do insects. That means they will lose or gain moisture from their environment. If they lose too much water, that will result in desiccation and if they gain too much water, that is also lethal. When you see them migrating out of rain soaked areas, they are trying to keep from dying by gaining too much moisture. The ones that do escape from the excess moisture will die quickly in the drier environment found within structures or on drying surfaces. Dead lawn shrimp are easily swept or vacuumed up and discarded.
There are no insecticides labeled for use on lawn shrimp, however, an application of a residual insecticide will accelerate their mortality in homes.
If lawn shrimp are a regular problem on sidewalks, patios or in structures after rains, you’ll need to find a way to help dry out the mulch or ground cover near these areas. Excessive moisture conditions can often be corrected by improving drainage and by reducing irrigation. Weather stripping on the bottom of doors will help to keep these pests out.
During rainy weather, you may also find large numbers of these pests in swimming pools and they may even cause your pool filters to clog. So, it is important that you service your filters on a regular basis. Never apply any insecticides near a swimming pool.
The key to solving lawn shrimp problems is to control moisture. By reducing moisture, you will significantly reduce their population and you’ll have much less of a problem during the rainy season. Do you need help with these or other pests? Call our office at (949) 631-7348 and we’ll be happy to schedule an appointment at your convenience.
